He told Uefa.com: "I am excited and happy in the same time, also very proud that I am going to play in such a big club.
"Every football player wants to play for Barcelona, Real (Madrid), Manchester United or Arsenal one day and so do I.
"I want to progress in my career, but it will be hard to leave Dinamo Zagreb after eight years.
"I will miss the club, the guys. I will be back one day, but now I want to accept a new challenge."